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A099865
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Numerator of sum of all elements M(i,j,k) = i*j/k, (i,j,k = 1..n). a(n) = Numerator[Sum[Sum[Sum[i*j/k,{i,1,n}],{j,1,n}],{k,1,n}]].
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1
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1, 27, 66, 625, 2055, 21609, 10164, 123282, 320805, 4465505, 920821, 14537549, 104285363, 41010655, 47830280, 2816662204, 6447760119, 139131611847, 26153100905, 29313445875, 13068630729, 111103313343, 91973556693
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) = Numerator[Sum[Sum[Sum[i*j/k, {i, 1, n}], {j, 1, n}], {k, 1, n}]]
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EXAMPLE
| Sum[M(i,j,k)] begins 1, 27/32, 66, 625/3, 2055/4, 21609/20, ... So a(4) = 625.
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MATHEMATICA
| Table[ Numerator[ Sum[ i*j/k, {i, n}, {j, n}, {k, n}]], {n, 23}]
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CROSSREFS
| Corresponding denominator of Sum[M(i, j, k)] is A099866
Cf. A099866.
Sequence in context: A088248 A078111 A106200 * A065008 A116353 A116302
Adjacent sequences: A099862 A099863 A099864 * A099866 A099867 A099868
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KEYWORD
| nonn,frac
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AUTHOR
| Alexander Adamchuk (alex(AT)kolmogorov.com), Oct 28 2004
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